Drilling fixture for spherical objects



I March 7, 1961 J. A. HLADIK 2,973,674 DRILLING FIXTURE FOR SPHERICAL OBJECTS Filed May 28, 1958 2 Sheets-Sheet 1 INVENTOR.

JOSEPH A. HLADIK ATTORNEY March 7, 1961 J. A. HLADIK DRILLING FIXTURE FOR SPHERICAL OBJECTS 2 Sheets-Sheet 2 Filed May 28, 1958 JOSEPH A. HLADIK a2 BY I8 A T TORNE Y make up the drawings.

United States Patent O 2,973,674 DRILLING FIXTURE FOR SPHERICAL OBJECTS Joseph AntonHladik, Cicero, Ill., assignor to American The present invention relates to a drilling apparatus for spherical objects and more particularly to a work holder for use in spacing and drilling grip holes in bowling balls.

In work holders presently available, in order to properly locate the portion of the ball to be drilled by a conventional drill press, a complicated device is required employing tilting arbors and necessitating multitudinous adjustments. Most bowling balls are drilled to a particular bowlers physical requirements which is generally done by a local bowling establishmentproprietor to his customers specific order. Since these proprietors are rarely highly-skilled machinists, the use of complicated ball drilling fixtures of the type described above is slow and often results in inaccuracies in the distance between the holes and the pitch thereof- I The present invention is characterized by the provision of a bowling ball drilling fixture or jig which is simple in design and operation yet capable of vlocatingQwith a high degree of accuracy, desired portions of a bowling ball relative to the rigid straight shank of the drill in a conventional drill press. The present invention is provided with means for aligning the drill of the drill press with the center of the ball support of the jig. The invention is likewise provided with a base movable by the actuation of calibrated means, such as hand wheels to locate any selected portion of a ball held inthree point grip'on the'ball support thereof in any horizontal position relative to the drill such that thumb andfinger.

holes in the ball may be. quickly and accurately drilled. It is therefore an object of the present invention to provide a novel holder for a bowling ball to be drilled. It is another object of this invention to provide a simple, novel holder for a bowling ball to be drilled wherein the base of the fixture is movable to locate portions of a ball thereon in any horizontal position relative to a drill.

It is a further object of this invention to provide a" simple ball drilling fixture having a minimum of'moving parts. 7

It is an added object of the present invention to pro vide a bowling ball drilling fixture with a calibrated means for positioning portions of a ball such that finger 'holes may be drilled therein in pre-determined spaced relationship and with pre-determined pitch, where this is desired. i

It is an additional object of this invention to provide a bowling ball drilling jigwith means for aligning the jig relative to the drill of a drill press.

Other objects and features of the invention will appear as the description of the particular physical embodiment selected-to illustrate the invention progresses. In the accompanying drawings, which form a part of this specification, like characters of reference have been applied to corresponding parts throughout the several views which Fig. 1 is a perspective view of the operative association with a drill press.

Fig. 2 is a plan" view of the invention.

Fig. 3 is a view, taken along line 3-3 of Fig. 2.,

Fig. 4- is a side elevation of the'invention.

2,973,674 Patented Mar. 7, 1961 ice ated with a drill press D. Drill press D can be any of the'conventional types generally available. Ball drilling jig or fixtures, designated generally 10, is set on the base b of drill press D below the bit or shank S thereof and the entire assembly suitably secured to the top of work table T.

Jig 10 comprises a pair of movable plates 12 and 14. Lower plate 14 is provided with a central longitudinal groove or channel 16 which slidably accommodates bracket 18. Bracket 18 is suitably secured to base b as by screws 20. Bracket 18 is provided at one end with an upright member'22. Fixed to an edge 15 of lower plate 14 is a second bracket 24 also slidably mounted on bracket 18. Threaded shaft 26 is rotatably secured at one end in member 22 by collar 28 while its other end is threaded through bracket 24. Hand wheel 30 is mounted on the end of shaft 26 in extension 22 such that when hand Wheel 30 is actuated, lower plate 14 moves relative to bracket 18, it being understood that due to the connections detailed below both plates 12 and 14 move together relative to bracket 18 when hand wheel 30 is actuated. Also, lower plate 14 is provided with a central aperture 17 1 Upper plate 12 is provided with spaced longitudinal- I grooves or channels 32 and 34 generally at right angles to. channel 16 of lower plate 14. Aligning bars 36 and 38.

1 are fixed to plate 14 as by suitable machine screws 40 Formed on an edge 13 of upper plate 12 is a lug 40. Lower plate 14 is provided with an extended portion 42' which terminates in an upright section 44. Section 44 is preferably at right angles to members 22 and 24, as

1 shown in Figures 1 and 2. A threaded shaft 46 is rotatably secured at one end in section 44 by collar 48 while its other end is threaded through lug 40. Hand wheel 50,

is mounted on the end of shaft 46 in section 44 such that when hand wheel 50 is rotated, upper plate 12-moves relative to lower plate 14. Slot 52 is provided in the upper surface of plate 12 to accommodate the travel of shaft 46 through lug 40. V A calibrated scale 54, secured to the upper surface of lower plate 14 adjacent edge 15 thereof, as shown in Figure 2, is provided to indicate the amount of relative, movement between plates 12 and 14. Upper plate has a cut-out portion 56 with an indicator mark 58 such that when mark 56 is at zero on scale 54, plates 12 and 14 are perfectly aligned as shown in Figure 2. M

A second calibrated scale 60, secured to the upper surface or bracket 18adjacent bracket 24 as shown in,

Figure-2, is provided to indicate the amountof relative movement between plate 14 and bracket 18. Edge 23 of bracket 24 serves as an indicator such that when edge 23 is aligned with the zero mark of scale 60, the plates 12v and 14 and bracket 18 are in' proper alignment.

present invention in Thumb screws 59 and 6l thre'aded through the top of bracket 24 and lug 40 respectively operate to secure shafts 26 and 46 in position therein.

Mounted on the upper surface of upper plate 12 are two upright standards 62 and 64 of generally T cross-' section in plan. Standards 62 and 64 are preferably located on plate 12 at each corner thereof adjacent extended portion 42 as shown in Figure 2. Standards 62 and- 64 are shown as an integral part of plate 12 but, if

desired, may-be separately formed and suitably secured Referring specifically to'Figure .1, a preferred embodiment of the invention is shown operatively associ thereto. Snubbers 66, preferably of a resilient material such asrubber, are secured to the inner faces of eachstandard 62 and 64adjacent the topmost .portion thereof Q MF Pisa??? 3 P .1-

A bracket 68 is formed on or secured to the upper surface of plate 12 opposite lug 40. Arm 70 is swingahly mounted for movement in a substantially vertical plane, as viewed in Figures 3 and 4, on pivot pin 72 supported in bracket 68. A threaded shaft 74 is threaded through and mounted for rotation in the free end of arm 70. An operating knob 76 is secured to one end of shaft 74 and a snubber 78, preferably of resilient material, is fixed to the other such that when knob 76 is actuated, snubber 78 is moved into and out of engagement with a bowling ball B on plate 12. Arm 70 is also provided with a lower extension 80 which alternately engages spaced studs 82 and 84 secured to edge 11 of plate 4 and bracket 68 respectively. It will be understood that studs 82 and 84 limit the amount of travel of arm 70 in pivoting about pin 72 (see Figure 4). The central portion of plate 12 is provided with an opening 86 which accommodates removable ball rest 88 also preferably of resilient material.

As can be noted from Figures 2 and 3, shaft 74 is preferably provided with left hand threads. This insures that when knob 76 is rotated to move snubber 78 into ball engaging position, snubber 78 will be pressed inwardly against ball B and thus not tend to skew away from it as would be the case if shaft 74 were provided with right hand threads. It will likewise be noted that by providing shaft 74 with a left hand thread when force is applied to knob 76 to secure ball rest 88, the torque applied thereto will be in a direction such that extension 80 on arm 70 will be urged against stud 82 rather than away from it as would be the case if shaft 74 had right hand threads. It will be understood however, that if shaft 74 had right hand threads the operation of the mechanism would still essentially be the same.

In operation, jig must first be properly aligned with shank S of a drill d in drill press D. To accomplish this, hand wheels 30 and 50 are actuated until their associated scales are at their respective zero positions, as described hereinabove. Thumb screws 59 and 61 are turned down to secure their associated shafts 26 and 46 in position, preventing further relative movement either between plates 12 and 14 or plate 14 and bracket 18. Next ball rest 88 is removed from opening 86 and is replaced by an upright aligning pin 90. Jig 10 is moved on base b until pin 96 is directly beneath shank S as shown in Figure 1. When pin 90, drilled and shank S are in the positions shown in Figure 1 and scales 54 and 60 are at zero, jig 19 is properly aligned with shank S of drill press D. Bracket 18 is then secured to base b of drill press D by screws 20 as described hereinabove. Aligning pin 90 is removed and replaced by ball rest 88 and jig 10 is ready to receive a bowling ball Bto be drilled.

A bowling ball is generally provided with three spaced gripping holes; namely, a thumb hole and two finger holes. The spacing of these holes and their diameter will vary according to the particularphysical characteristics and desires of the bowler. To ensure proper rolling characteristics, bowling balls are normally manufactured so that their weight is non-uniform, the ball being heavier on one side than the other. This is to compensate for the later drilled gripping holes. The weighted side is so marked by the manufacturer in order that the finger holes will be placed on the proper side of the ball by the person drilling the gripping holes. The desired spacing is then laid out on the surface of the ball, usually relative to a plane through this marking and the center of the ball. The thumb hole is generally drilled on this plane while the finger holes generally are drilled equidistantly spaced therefrom. a a

Thumb holes are generally given an inclination called pitch, either forward or reverse, as the bowler desires. This pitch facilitates gripping and ball control by the bowler. To provide the thumb hole with pitch, for are ample, the usually-preferred forward pitch, thumb screw 59 is loosened. Handwheel is then actuated such that plates 12 and 14 move relative to bracket 18 toward the back of drill press the desired amount of pitch by edge 23 as determined on scale 60. Thumb screw 59 is then re-tightened securing plates 12 and 14 in offset position. Thus any holes in ball B drilled by shank S while plates 12 and 14 are in this position are in a plane offset fiom a plane through the center of ball B, providing forward pitch to such holes. It will be understood that to provide reverse pitch, handwheel 30 is actuated to move plates 12 and 14 forwardly on bracket 18 away from the back of drill press D.

A bowling ball B, to be drilled in pre-determined points on its circumference in accordance with the particular desired specifications of a bowler, is placed on ball rest '88 adjacent snubber 66. A drill d of the size required by the bowlers thumb is placed in shank S, arm pivoting to the position shown in broken lines in Figure 4 to facilitate placement of ball B on ball rest 88. Ball B is oriented on ball rest 88 such that the predetermined location of the thumb hole is directly beneath the shank S of drill press D. Arm 70 is pivoted to its vertical position shown in Figure 4 and knob 76 actuated to move shaft 74 in arm 70 such that snubber 78 engages the surface of ball B securing ball B firmly in position or clamped in jig 10, between snubbers 66 and 78 at spaced points, preferably apart on the circumference of ball B. Further, to ensure the best clamping action, snubbers 66 and 78 are located vertically such that they engage ball B at space/:l points along the major horizontal plane through the center of ball B.

Drill press D is then actuated from a suitable power source (not shown) to rotate shank S to drill the thumb hole. Drill press D is stopped when the thumb hole has been drilled to the desired depth based on the length of the bowlers thumb. Drill d is removed from the drilled thumb hole in ball B and knob 76 again actuated,

this time to move snubber 78 out of engagement with ball B.

' To drill the finger holes, handwheel 30 is first actuated to return plates 12 and 14 to their aligned position on bracket 18, moving. edge 23 of bracket 24 back to its zero position on scale 60. The reason for this is that finger holes are not generally drilled with any pitch. However, if desired, finger holes could also be drilled with either forward or reverse pitch as described hereinabove in connection with the thumb hole.

With edge 23 at zero position on scale 60, ball B is oriented on ball rest 88 such that drill d of the size required by the finger holes, is directly over the reference plane for the hole markings and aligned with the location of the two finger holes to be drilled. Knob 76 is again actuated to secure or clamp ball B in drilling position in jig 10.

Next thumb screw 61 is loosened and handwheel 50 is actuated to move plate 12 relative to plate 14 shifting the position of ball B laterally with respect to drill d. Handwheel 50 is actuated until the lateral distance from the plane of reference for the first finger hole has been reached. This distance is a function of the physical characteristics of the bowlers and is indicated by the position of 58 along scale 54. It will likewise be understood that the drill sizes used in drilling the finger holes are functions of the physical characteristics of the bowler and while usually the finger holes are of the same diameter, if desired, a different diameter hole could be drilled by changing the size of drill d. When the proper lateral distance is reached, thumb screw 61 is retightened, securing plate 12in proper offset position relative to plate 14.

Drill press D is then re-actuated torotate shank S and drill the first finger hole to the desired depth. Shank 8 is then removed from within ball B and thumb screw 61 loosened. Handwheel '50 is then re-actuated to move b'all B such that the reference plane is again beneath, shank S and mark 58 is back'to its zero position on scale 54. Handwheel 50 continues to be operated moving ball B until the lateral distance 'inthe other direction from the reference plane is reached as evidenced by the position of indicator mark 58 on scale 54. When the proper lateral distance is reached for the second fingerhole, thumb screw 61 is tightened, securing plate 12 in its new oifset position relative to plate 14.

Drill press D is again actuated to rotate shank S and drill the second finger hole to the desired depth. Shank S is then removed from within ball B. Knob 76 is now actuated to move snubber 78 out of clamping engagement with ball B. Arm 70 is pivoted on pin 72 to the position shown in broken lines in Figure 4 to facilitate the removal of the drilled ball B from jig 10. Thumbscrew 61 is then loosened and handwheel 50 actuated to return plate 12 to its aligned position on plate 14, moving indicator mark 58 to its zero position on scale 54.

It will be understood that, if desired, the gripping holes in ball B secured in jig by snubber 78, can be reamed by any suitable means (not shown) such as, a brace and reamer. Ball B may be oriented on ball rest 88 as described above to facilitate access to the reaming tool.

Jig 10, back in its aligned position described at the start of the operation detailed above, is ready for the next ball B to be drilled in pre-determined points on its circumference in accordance with the particular specifications of its owner.

What I claim is:

1. A fixture for use with a drill to drill bowling balls comprising an upper plate, a removable ball support on said upper plate aligning said fixture relative to said drill, two fixed standards on said upper plate for engaging a bowling ball on said ball support, an arm pivotally mounted on said upper plate, a shaft threaded for movement in the free end of said arm, a knob on said shaft for rotating said shaft for movement in said arm, a snubber in pro-determined fixed ball-engaging position on each of said standards, a third snubber on the other end of said shaft for engaging-said ball on said ball support upon rotation of said shaft in said arm, fixedly clamping said ball in pre-determined orientation in said fixture between said snubbers when said arm is in substantially vertical ball-clamping position, stop means on said upper plate for limiting the movement of said arm when in vertical ball-clamping position, said thread on said shaft being constructed and arranged to urge said arm against said stop as said shaft is rotated therein to move said third snubber into ball-engaging position, maintaining said arm in vertical ball-clamping position, a lower plate, keyways in said upper plate, keys secured to said lower plate and slidably accommodated in said keyways in said upper plate, an extension on said lower plate, a second shaft rotatably supported in said extension, a threaded lug secured to said upper plate, said lug adapted for movement along said second shaft, a handwheel on said second shaft for rotating said second shaft whereby said upper plate is moved relative to said lower plate along said keyways, a bracket, said lower plate provided with an aperture slidably accommodating said bracket for movement substantially perpendicular to said keyways, a third threaded shaft, means on said bracket rotatably supporting said third shaft, a threaded second bracket secured to said lower plate, said threaded bracket adapted for movement along said third shaft, and a handwheel on said third shaft for rotating said third shaft whereby said upper and lower plates are moved together relative to and along said bracket in a direction substantially perpendicular to the direction of movement of said upper plate relative to said lower plate, the movement of said plates being operative to locate a bowling ball clamped between said standards at selected horizontal positions relative to said drill.

2. The invention as defined in claim 1 including a first calibrated scale on said lower plate for indicating the holes by the said jig relative to a drill, two fixed standards mounted on said upper plate, said fixed standards being of generally T-shaped horizontal cross-section, a clamp pivotally mounted on said upper plate, a shaft threaded for movement in the free end of said clamp, means on one end of said shaft for rotating said shaft for movement in said clamp, a rubber snubber at predetermined ballengaging height on each of said fixed standards, a third rubber snubber on the other end of said shaft coacting with said snubbers on said standards and operative when said shaft is rotated to engage a bowling ball on said ball support urging said ball into clamped position between said snubbers, spaced stops on said upper plate operative to engage :a portion of said clamp to limit the pivotal movement of said clamp therebetween from vertical ball-engaging position to inclined ball-release position, a lower plate, keyways in said upper plate, keys secured to said lower plate and slidably accommodated in said keyways in said upper plate, an extension on said lower plate, a second shaft rotatably supported-in said extension, a threaded lug secured to said upper plate, said lug adapted for movement along said second shaft, a handwheel on said second shaft for rotating said second shaft whereby said upper plate is moved relative to said lower plate along said keyways, a bracket, said lower plate provided with an aperture slidably accommodating said bracket, said aperture in said lower plate being substantially transverse to said keyways in said upper plate, a third threaded shaft, means on said bracket rotatably supporting said third shaft, a threaded second bracket secured to said lower plate, said threaded bracket adapted for movement along said third shaft, and a handwheel on said third shaft for rotating said third shaft whereby said upperand lower plates are moved together relative to and along said bracket in a direction substantially transverse to the direction of movement of said upper plate relative to said lower plate, a first calibrated scale on said lower plate for indicating the amount and direction of relative movement between said upper and lower plates, a second calibrated scale on said bracket for indicating the amount and direction of conjoint movement of said upper and lower plates relative to said bracket, said relative and conjoint plates being operative to travel portions of said bowling ball clamped between said snubbers to any selected horizontal position relative to said drill.

5. The invention as defined in claim 4 wherein said snubbers engage said ball at spaced coplanar points substantially apart on the horizontal diameter of said ball.

6. The invention as defined in claim 4 wherein said shaft is provided with means for biasing said clamp against one of said stops maintaining said arm in said vertical ball-engaging position as said shaft is rotated to move its associated snubber into ball engagement.

References Cited in the file of this patent UNITED STATES PATENTS 1,217,572 Craley Feb. 27, 1917 1,372,661 Secord Mar. 22, 1921 1,396,302 Wagner Nov. 8, 1921 1,517,309 Morgan Dec. 2, 1923 2,283,469 Shepard May 19, 1943 

